This article considers capacity development processes within the movement of non‐indigenous people who support indigenous sovereignty in Aotearoa/New Zealand. Based on action research by a movement member, it explores if and how learning contributes to the overall capacity development of the movement. The research focused on learning with regard to the relationship‐based practice of working with Mäori activists. It highlights the unintentional, informal and embedded nature of this learning. While individuals were engaged in ongoing learning, there was limited sharing of learning within the movement. In exploring the reasons for this, the complexity of facilitating capacity development with regard to relationship‐based practice becomes evident. Capacity development through learning within this social movement was largely unintentional. Two intentional processes are identified as being important means of facilitating capacity development within a social movement: the informal process of intergenerational questioning and the structured process of action research.